France is considered a Mediterranean country. Although it is not a coast in the Mediterranean, it is considered as a Mediterranean country due to its historical and cultural similarities.
Its surface area is 2,, km 2 , its length is 3, km, the widest place is 1, km, its deepest point is 4, m. The width of km between Sicily and the Bon Cape of Tunisia divides the Mediterranean into two as east and west. The salinity is very high compared to the Atlantic Ocean.
Tidal events show very small changes. Coasts are usually mountainous, often earthquakes and volcanic events are seen. From the south, hot, dry, sirokko, from the north, cold, dry, mistral and bora local winds are seen. During the Triassic period about million years ago , the land mass of the world was divided into two mainlands of almost the same size: Laurasia in the north, Gondwana in the south.
When the masses of Laurasia and Gondwana formed and disintegrated, these two mainlands were filled with the Tethyan Sea.
The last form of the Mediterranean today was formed by the pressure of the north, which began at the end of the Cretaceous period about 65 million years ago and lasted until the end of the Miocene period 13 million years ago.
This mass also formed the curved mountain ranges surrounding the present Mediterranean Sea, causing the sedimentary masses in the Tethyan Sea to compress, bend and swell.
The hydrology and water structure of the Mediterranean is under the influence of the high evaporation rate of the high temperature of the basin. The water structure lost by the Mediterranean is The rate of water lost by evaporation is higher than the rate of precipitation, which is the main reason for the high salinity rate. Temperature changes in the Mediterranean Basin are reflected in the waters. The Mediterranean climate is cool and rainy in winter, warm and dry in the summer has revealed an extraordinary vegetation.
The main vegetation in the dryest parts of the basin was formed by the post-glacial period forests leaving their places in the scrub vegetation.
This vegetation, which consists of countless species, adapts to hot and dry summer months with its thin leaves that reduce evaporation. Region-specific, large tree species are conifers, olive and oak trees. The majority of fish communities and shellfish living in the Atlantic Ocean live in the Mediterranean. The Italian Adriatic coast, revealing the Apennines, is typical of an emerged coast. The granite coast of north eastern Sardinia and the Dalmatian coast where the eroded land surface has sunk, producing elongated islands parallel to the coast, are typical submerged coasts.
The Mediterranean Sea is a semi-enclosed sea characterized by high salinities, temperatures and densities. The net evaporation exceeds the precipitation, driving an anti-estuarine circulation through the Strait of Gibraltar, contributing to very low nutrient concentrations. The Mediterranean Sea has an active overturning circulation, one shallow cell that communicates directly with the Atlantic Ocean, and two deep overturning cells, one in each of the two main basins Tanhua et al. It acts like an ocean system in which several temporal and spatial scales basin, sub-basin and mesoscale interact to form a highly complex and variable circulation.
It is one of the few locations in the world where deep convection and water mass formation take place. The Mediterranean is also an important marginal basin to the North Atlantic producing very saline waters, the outflow of which through the Strait of Gibraltar may play an indirect role in the deep circulation of the North Atlantic.
The Mediterranean hydrodynamics are driven by three layers of water masses: a surface layer, an intermediate layer, and a deep layer that sinks to the bottom.
The Mediterranean Sea receives from the rivers that flow into it only about one-third of the amount of water that it loses by evaporation. In consequence, there is a continuous inflow of surface water from the Atlantic Ocean. After passing through the Strait of Gibraltar, the main body of the incoming surface water flows eastward along the north coast of Africa.
This current is the most constant component of the circulation of the Mediterranean. It is most powerful in summer, when evaporation in the Mediterranean is at a maximum. This inflow of Atlantic water loses its strength as it proceeds eastward, but it is still recognizable as a surface movement in the Sicilian channel and even off the Levant coast.
A small amount of water also enters the Mediterranean from the Black Sea as a surface current through the Bosporus, the Sea of Marmara, and the Dardanelles Coll et al. The Mediterranean region is characterized by winter dominated rainfall and hot dry summers. Even though large spatial climate variability and diversity exist within the Mediterranean basins, many areas can be classified as arid or semiarid.
The Mediterranean is an area of transition between a temperate Europe with relatively abundant and consistent water resources, and the arid African and Arabian deserts that are very short of water.
The Mediterranean region is experiencing a large stress on its water resources due to a combination of effects ranging from climate change to anthropogenic pressures due to an increasing water demand for domestic and industrial use, expansion of irrigated areas, and tourism activities. These resources are unevenly distributed over space. Water resource availability in the Mediterranean has already been affected by environmental change, and is seriously jeopardized in future environmental, economic, and demographic scenarios Garcia-Ruiz et al.
Most global hydrological models are based on expected trends in precipitation and temperature. However, a number of studies have demonstrated the influence of land cover on river discharge and water resources. Climate and land cover change artificial and natural reforestation, deforestation, expansion of farming areas are likely to amplify water stress in the Mediterranean region, caused by a combination of decreased water resource availability lower precipitation and increased evapotranspiration and increased water use pressure resulting from economic growth and urban expansion.
Special attention to mountain areas is required, as they are the most important sites for water resource generation worldwide, and particularly in temperate and semi-arid areas including the Mediterranean basin. However, mountain areas are facing increasing hydrological stress caused by a combination of i increasing temperature and decreasing precipitation, exceeding that in the lowlands; ii land use change, including natural and deliberate reforestation of abandoned farmland, thus increasing evapotranspiration and water consumption; and, iii increasing pressures on surface and groundwater resources, thus reducing river discharge and lowering the depth of the water table in groundwater-dependent areas.
The amount and distribution of rainfall in Mediterranean localities is variable and unpredictable. Maximum precipitation is found in mountainous coastal areas Figure 1.
The climate in the region is characterized by hot, dry summers and cool, humid winters. The annual mean sea surface temperature shows a high seasonality and important gradients from west to east and north to south. Coastal aquifers provide another source of freshwater discharge to the Mediterranean. The submarine groundwater discharge from the coastal aquifers, estimated at 2. Seepage inflows are prevalent on the eastern coast of the Adriatic, dominated by karstic aquifer systems, as well as on the eastern and southern Mediterranean coast with semi-arid and arid conditions, limited precipitation and runoff, and limited surface watercourses and discharge points.
Coastal seepage and submarine discharges are critical to the water balance and seawater quality in the marine sub-basins. They also support wetlands and brackish water habitats, important to biodiversity, and fishery nursery areas. The coastal aquifers are threatened by over-exploitation and consequent seawater intrusion and water and land salinisation, which will add to the deficit in recharge of the Mediterranean.
With a typical tidal range of less than 50 cm, the Mediterranean Sea is microtidal. This reduces the potential for dilution and dispersion of dissolved and particulate wastes. It is also one of the most oligotrophic i. The main source of nutrients in the Mediterranean lies in the inflowing Atlantic surface waters at the level of the Gibraltar Strait. These inflowing waters flow eastward along the African coasts in the western Mediterranean, then cross the Sicily Strait and continue their flow again along the northern African coasts.
As the waters move eastwards from the Gibraltar Strait, they become depleted in nutrients.
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